Algae connected like a raft

Four individual algal cells are connected, forming a colony shaped like a raft, which allows it to float freely in water. This colony is standing still by the side of a particle.

Commentary by Prof. Yuji Tsukii, Hosei University
This organism is a mature Scenedesmus quadricauda.

http://protist.i.hosei.ac.jp/PDB/Im.....

Once I happened to exchange e-mail with Dr. Eberhard Hegewald, a specialist in Scenedesmus classification living in England. Subsequently I bought his text book and found pictures of various kinds of Scenedesmus and their related species. The overwhelming data and illustrations make it difficult to determine the exact species of this organism, but generally speaking it must be S. quadricauda.

Sampling Date : 02 July 2009

Sampling Site : Hirose River A  Google Map